CUMULATIVE COMPOUNDING DAN

Cumulative Compounding : Medan seri

Short Shunt Compound Generator

Long Shunt Compound Generator

Over, Flat and Under Compound

(i) If series winding turns are so adjusted that with the increase in load currentthe terminal voltage increases, it is called over-compounded generator. Insuch a case, as the load current increases, the series field m.m.f. increasesand tends to increase the flux and hence the generated voltage. Theincrease in generated voltage is greater than the IaRa drop so that insteadof decreasing, the terminal voltage increases .(ii) If series winding turns are so adjusted that with the increase in loadcurrent, the terminal voltage substantially remains constant, it is called flatcompounded generator. The series winding of such a machine has lessernumber of turns than the one in over-compounded machine and, therefore,does not increase the flux as much for a given load current. Consequently,the full-load voltage is nearly equal to the no-load voltage.(iii) If series field winding has lesser number of turns than for a flat compoundedmachine, the terminal voltage falls with increase in load current. Such amachine is called under-compounded generator.

Soal 1: Hitung Pg

Soal 2: hitung besarnya flux magnit

Soal 3: hitung Pg jika bebannya adalah 60 buah lampu @ 40 W

Soal 4 : Hitung Eg jika voltage drop pada brush adalah 1

V/brush

Soal 5: hitung Eg jika brush voltage drop = 1V/brush

Soal 6: Hitung Eg untuk kondisi tanpa Rdiv dan dengan Rdiv

KURVA MAGNETISASI

Pengukuran kurva jenuh

Kharakteristik Generator DC eksitasi terpisah

Kharakteristik Generator DC Seri

Kharakteristik Generator DC Shunt

Load Characteristic shunt generator

(i) O.C.C.The O.C.C. of a shunt generator is similar in shape to that of a seriesgenerator as shown in Fig. The line OA represents the shunt field circuitresistance. When the generator is run at normal speed, it will build up avoltage OM. At no-load, the terminal voltage of the generator will beconstant (= OM) represented by the horizontal dotted line MC.(ii) Internal characteristicWhen the generator is loaded, flux per pole is reduced due to armaturereaction. Therefore, e.m.f. E generated on load is less than the e.m.f.generated at no load.As a result, the internal characteristic (E/Ia) dropsdown slightly as shown in Fig..(iii) External characteristicCurve 2 shows the external characteristic of a shunt generator. It gives therelation between terminal voltage V and load current IL.V = E IaRa = E -(IL +Ish)RaTherefore, external characteristic curve will lie below the internalcharacteristic curve by an amount equal to drop in the armature circuit [i.e.,(IL +Ish)Ra ] as shown in Fig.